Rotary apparatus

ABSTRACT

A rotary machine ( 10 ) comprises an inner housing ( 12 ) having valving means ( 14 ) which includes a shaft ( 15 ) for directing working fluid through the machine ( 10 ) and, an outer housing ( 16 ) within which the inner housing resides. A working chamber ( 18 ) is defined between the inner and outer housings ( 12  and  16 ). A plurality of gates ( 20 ) are supported by the inner housing and are swingable along their respective longitudinal axis between a sealing position in which the gates form a seal against surface ( 22 ) of outer housing ( 16 ) and a retracted position in which the gates ( 20 ) lie substantially against surface ( 24 ) of the housing ( 12 ).

FIELD OF THE INVENTION

The present invention relates to a rotary machine.

BACKGROUND OF THE INVENTION

Throughout this specification including the claims, the term “rotarymachine” is intended to include both motors and pumps that act oroperate on, or, are driven or otherwise operated by, a fluid.

Rotary machines have been known and used in various industries eversince the industrial revolution. In general terms, when operated as amotor, a high pressure fluid is fed through the machine and the pressureof the fluid used to impart motion to mechanical components to generatea mechanical kinetic energy used to power or drive some other machine.When operated as a pump, mechanical power is imparted to movingcomponents of the pump which displace or force fluid through the machineto create a fluid flow and thus a pumping action.

The Applicant has been particularly innovative in the design andmanufacture of rotary machines including, although not limited to,rotary machine for use as motors in oil and gas directional drilling. Anexample of such a rotary machine, configured as a motor is described inInternational Application No PCT/AU97/00682. A substantial benefit ofthe motor described in the aforementioned application is that, incomparison with other known motors, it has a substantially higher powerdensity or power to weight ratio. This enables the motor to be of asignificantly shorter length for the same power output as a conventionalmotor. This allows greater precision in directional control of adirectional drill and the ability to turn at substantially smaller radiithat can be achieved with the prior art.

Notwithstanding the substantial benefits of the motor described in theaforementioned application, the Applicant continues to conduct researchand development in the area of rotary machine design. This research anddevelopment has led to the invention described herein.

SUMMARY OF THE INVENTION

According to the present invention there is provided a rotary machineincluding at least:

-   -   an inner housing;    -   an outer housing in which the inner housing resides, one of the        inner and outer housings being rotatable relative to an other of        the inner and outer housings, with a working chamber through        which a working fluid flows being defined between the inner        housing and the outer housing;    -   a plurality of gates supported by one of the inner housing and        the outer housing (hereinafter “the supporting housing”), each        gate swingable along its respective longitudinal axis between a        sealing position in which the gates form a seal against a        surface of the other one of the inner housing and outer housing        (“the non-supporting housing”) facing the working chamber and, a        retracted position in which the gates are swung about their        longitudinal axes to lie substantially against a surface of the        supporting housing facing the working chamber; and,    -   valve means operatively associated with said supporting housing        for directing working fluid into said working chamber via said        support housing.

Preferably the supporting housing is provided with a plurality ofsockets extending longitudinally along its surface facing the workingchamber and each gate is pivotally retained and supported in arespective socket to facilitate the swinging motion of the gates.

Preferably the sockets and the gates are complimentarily shaped so thatwhen the gates are in the retracted position their radially outermostsurface lies substantially flush with, or below, the surface of thesupporting housing facing the working chamber.

Preferably each socket and each gate is provided with a first set ofrespective stop surfaces that come into mutual abutment when the gatesswing to the sealing position from the retracted position.

Preferably each socket and gate is provided with a second set ofrespective stop surfaces spaced from the first set of stop surfaces havecome into mutual abutment when the gates swing to the sealing positionfrom the retracted position.

Preferably said first and second sets of respective stop surfaces arepositioned so as to come into respective mutual contacts substantiallysimultaneously.

Preferably the supporting housing is provided with a plurality of inletports providing fluid communication between the valve means and theworking chamber.

Preferably each inlet port has an opening into said working chamber andsaid gates are arranged to overlie said opening when in the retractedposition wherein fluid passing through the inlet port urges said gatetoward said sealing position.

Preferably the non-supporting housing is provided with a plurality oflobes each of which forms a seal against the surface of the supportinghousing facing the working chamber to divide the working chamber into aplurality of sub-chambers, said lobes configured to force said gatestoward said retracted position upon engagement of the lobes with thegates.

Preferably said non-supporting housing is provided with at least oneexhaust port for each sub-chamber for exhausting fluid entering asub-chamber.

In one embodiment when the supporting housing is the inner housing thevalve means is in the form of a shaft extending coaxially into androtatable relative to the supporting housing, the shaft having an axialpassage in fluid communication with a supply of said working fluid and aplurality of radially extending holes providing fluid communicationbetween said axial passage and the inlet ports in the supporting housingfor a predetermined period of time per revolution of the shaft relativeto the supporting housing.

Preferably said valve means is provided with adjustment means tofacilitate adjustment of the flow of said fluid into said inlet ports.

Preferably said adjustment means includes a sleeve located coaxiallywith the shaft and moveable relative to the shaft, said sleeve providedwith one or more apertures extending radially therethrough, and meansfor effecting movement of said sleeve relative to said shaft to allowvariation in overlap or alignment of the apertures and the holes tothereby control the flow of said working fluid from said supply to theinlet ports.

Preferably said means for effecting movement includes coupling actingbetween the outer housing, a connector used for connecting the rotarymachine to a supporting apparatus and, one of the shaft and the sleeve;whereby a torque differential between the outer housing and thesupporting apparatus is transmitted by said coupling to act between saidsleeve and said shaft to effect said movement of the sleeve relative tothe shaft.

In an alternate embodiment, when the supporting housing is the outerhousing, said valving means comprises a plate disposed coaxially of theouter housing, the plate provided with a feed channel on a side distantthe supporting housing in fluid communication with a supply of workingfluid and a plurality of slots cut in the axial direction through theplate for providing fluid communication between said feed channel andthe inlet ports in the supporting housing for a predetermined period oftime per revolution of the plate relative to the supporting housing.

In this alternative embodiment the inlet ports extend axially though theouter housing and open at an end of the housing adjacent the plate.

BRIEF DESCRIPTION THE DRAWINGS

Embodiments of the present invention will now be described by way ofexample by way of example only with reference to the accompanyingdrawings in which:

FIG. 1 is a schematic representation of a partial assembly of a rotarymachine in accordance with one embodiment of this invention;

FIG. 2 is a perspective view of an inner housing incorporated in therotary machine shown in FIG. 1;

FIG. 3 is a perspective view of an outer housing incorporated in therotary machine shown in FIG. 1;

FIG. 4 is a longitudinal section view of a rotary machine incorporatingthe components shown in FIGS. 1-3;

FIG. 5 is a cross-sectional view of the rotary machine shown in FIG. 4;

FIG. 6 is a cross-sectional view of a second embodiment of the rotarymachine;

FIG. 7 is a longitudinal section view of third embodiment of the rotarymachine;

FIG. 8 is a cross-sectional view of the rotary machine shown in FIG. 7;

FIG. 9A is a cross-sectional view of a fourth embodiment of the rotarymachine;

FIG. 9B is a longitudinal section view of the rotary machine shown inFIG. 9A;

FIG. 9C is an enlarged view of a portion of the machine depicted in FIG.9A with its exhaust system open;

FIG. 9D is an enlarged view of a portion of the machine shown in FIG. 9Bbut with the exhausting system shut;

FIG. 10 is a cross-sectional view of a fifth embodiment of the rotarymachine;

FIG. 11 is a perspective view of the outer housing of the fifthembodiment of the rotary machine shown in FIG. 10.

FIG. 12 is a perspective view of a valving plate for directing workingfluid into the working chamber of the fifth embodiment of the rotarymachine depicted in FIG. 10;

FIG. 13 is a longitudinal section view of a compound rotary machinecomposed of the first and fifth embodiments of the rotary machinecoupled in series;

FIG. 14 is a longitudinal section view of a further compound rotarymachine composed of two rotary machines in accordance with the firstembodiments coupled in series;

FIG. 15 is a perspective view of a further embodiment of the rotarymachine;

FIG. 16 is a cross-sectional view of the machine shown in FIG. 15; and

FIG. 17 is a perspective view of a supporting housing with coupled gatesincorporated in the machine depicted in FIGS. 15 and 16.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring to the accompanying drawings and in particular FIGS. 1-5, itcan be seen that the rotary machine 10 comprises an inner housing 12provided with a valve 14 comprising a member 17 in the form of a shaft15 that directs working fluid through the machine 10 and, an outerhousing 16 in which the inner housing 12 resides. The inner and outerhousings 12 and 16 are formed coaxially of each other with one of thehousings being rotatable relative to the other about a common axis. Aworking chamber 18 through which the working fluid flows is definedbetween the inner housing 12 and the outer housing 16. A plurality ofgates 20 a-20 f (referred to in general as “gates 20”) are supported inthis embodiment, by the inner housing 12. For convenience, the innerhousing 12 is therefore referred to as the “supporting housing 12”. Eachgate 20 is swingable along its respective longitudinal axis between asealing position in which the gates form a seal against surface 22 ofthe outer housing 16 that faces the working chamber 18 and, a retractedposition in which the gates 20 are swung about their respectivelongitudinal axes to lie substantially against the peripheral surface 24of the supporting housing 12 that faces the working chamber 18.

Throughout this specification and claims the term “seal” when used inrelation to describing the formation of a seal when a gate 20 is in thesealing position, is intended to include the formation of a substantialseal in which a small or controlled degree of leakage can occur. Asdescribed in greater detail hereinafter, the gates 20 when in thesealing position are spaced by a controlled distance from portions thesurface 22 of the non-supporting housing 16 other than the lobes. Theamount of clearance provided is dependent on the nature of the fluidpassing through the rotary machine 10. Generally the greater theviscosity or density of the fluid, the greater the clearance.

In the embodiment depicted in FIGS. 1-5 the supporting housing 12 (iethe inner housing 12) rotates (ie acts as a rotor) while thenon-supporting housing 16 is rotationally fixed (ie acts as a stator).Further, the shaft 15 is fixed relative to the non-supporting housing16.

The supporting housing 12 can be considered to be a cylindrical lengthof material provided with an axial bore 26 and a plurality of sockets 28extending longitudinally along its outer peripheral surface 24. Thesockets 28 are evenly spaced about the circumference of the supportinghousing 12. The sockets 28 have, in general, a shape that iscomplimentary to the shape of the gates 20 so that when the gates are inthe retracted position (depicted by gates 20 a, 20 c and 20 e in FIG. 5)the radially outermost surface of each gate 20 is flush with or set backfrom the surface 24 of the supporting housing 12.

Each socket 28 has a first portion 30 of arcuate shape when viewed inplan and a contiguous second portion 32. The first portion 30 is boundon opposite sides by a step 34 that leads to the second portion 32 and aridge 36 that leads to the arcuate, radially outermost portion 42 ofperipheral surface 24. The step 34 leads to a planar inclined seat 38. Aradially distant edge of the seat 38 terminates in a step 40 leading tothe arcuate radially outermost portion 42.

The supporting housing 12 is also provided with a plurality of radiallyextending inlet ports 44 that provide fluid communication between theshaft 12 and the working chamber 18. The inlet ports 44 open: at theirradially outermost end onto seats 38 on the supporting housing 12 and,at their radially innermost end onto the circumferential surface of thebore 26. The inlet ports 44 are arranged in rows that extendlongitudinally along the seats 38.

The gates 20 have, in transverse section, a shape somewhat like a commahaving an arcuate root 46 and a depending leg 48. The root 46 is shapedso that it can be slid into the first portion 30 of the socket 28 and toallow the gate 20 to swing along its longitudinal axis within the socket28. Indeed the coupling of the gates 20 with the sockets 28 is somewhatakin to the human hip joint. The gates 20 are formed as longitudinalelements of the same length as the sockets 28. A flat 50 is formed alongone side of the root 46 contiguously with the leg 48 so as to create astep 52 in the root 46. A further step 54 is formed on the opposite sideof the root 46 as a location where it adjoins the leg 48 (see forexample gates 20 b in FIGS. 1 and 5). The step 52 in gate 20 and thestep 34 in the socket 28 form respective first stop srrfaces that comeinto mutual abutment when the gate 20 is swung to the sealing position(as shown by gates 20 b, 20 d and 20 f in FIG. 5). This assists inproviding a predetermined clearance between the radially outermost endof gate 20 and the surface 22 of the non-supporting housing 16 (otherthan the lobes 64). Accordingly there is no surface to surface contactbetween gates 20 and the surface 22 (except on lobes 64) thussubstantially eliminating wear in this part of the machine 10. Thisclearance does allow for some leakage of the fluid but the clearance isarranged so that the leakage is controlled.

Further, the step 54 on gate 20 and step 36 on socket 28 form a secondset of respective stop surfaces that some into mutual abutment when thegate 20 is swung into the sealing position. This further assists inmaintaining the predetermined clearance. The degree of clearance for anyparticular application will depend on, among other things, the viscosityor density of the working fluid. The clearance can be varied byappropriate positioning of the steps 34, 52 and 54 and the ridge 36. Theabutment or engagement of steps 34 and 52; and ridge 36 and step 54,also provides support to the gates 20 when under load.

Referring to FIGS. 1, 4 and 5 the shaft 15 has an axial passage 56 influid communication with a supply of the working fluid, and a pluralityof radially extending holes 58 that provide a fluid communicationbetween the passage 56 and the inlet ports 44 in the supporting housing12. An upstream end of the shaft 15 is sealed with a plug 60. Thesupporting housing 12 rotates relative to the shaft 15. Accordingly theholes 58 are sequentially brought into and out of alignment orregistration with the inlet ports 44. The amount of fluid that can passfrom the shaft 15 to the working chamber 18 is dependent upon the areaof the opening of the holes 58 on the outer circumferential surface ofthe shaft 55. The greater the arc length of holes 58 the greater is thetime of registration between the holes 58 and the inlet ports 44. Thisprovides a mechanism for timing fluid pulsed into the working chamber18. It also brings about or facilitates the valving aspect of the shaft15 as in effect the shaft 15 opens and closes a fluid communication pathbetween the inlet ports 44 and the supply of the working fluid.

The non-supporting housing 16 is in the general form of an open-endedcylindrical drum. Extending axially from an upstream end of thenon-supporting housing 16 is a plurality of spaced apart lugs 62 (referFIG. 3). These lugs are configured to engage corresponding recesses in astring connector 63 (shown in FIG. 4) used to connect the motor 10 to adrill string. The engagement of the lugs in the recesses enables torqueto be coupled from the drill string to the supporting housing 16. Aplurality of lobes 64 (in this case three) are provided longitudinallyalong the surface 22 of the non-supporting housing 16. The lobes have aradially innermost surface 66 that is concavely curved to match thecurvature of the arcuate portion 42 of the peripheral surface 24 of thesupporting housing 12, as well as the curvature of the radially outersurface of the legs 48 of gates 20 when the gates 20 are in the sealingposition. The lobes 64 together with the supporting housing 12 dividethe working chamber 18 into three sub-chambers 18 a, 18 b and 18 c beingrespective sectors of the working chamber 18 located between mutuallyadjacent lobes 64. As explained in greater detail below, thesub-chambers 18 a, 18 b and 18 c are further divided by gates 20 when inthe sealing position.

An exhaust port 68 is formed in each of the lobes 64. The exhaust ports68 comprise an axially extending bore 70 formed through each lobe 64 anda plurality of feed holes 72 that pass transversely through the lobes 64to provide fluid communication between the working chamber 18 and thebore 70. The feed holes 72 are arranged in a longitudinal row along asurface 74 of each lobe 64 that joins the surface 66 to the surface 22.

Referring to FIG. 4, it can also be seen that the machine 10 is providedwith end plates 76 and 78 at opposite axial ends. The end plate 76 isessentially in the form of a disc having a central hole through whichthe shaft 15 extends. The end plate 76 is fixed to the supportinghousing 12 by one or more bolts 80. A bearing 82 is seated in a shoulderformed on the end plate 76 to allow for relative rotation between thesupporting housing 12 and the non-supporting housing 16.

The upstream end of the machine 10 is closed with the end plate 78. Theend plate 78 is provided with an axially extending drive shaft 83. Thedrive shaft 83 is provided with an internal passage 84 which is in fluidcommunication with the exhaust ports 68 formed in the non-supportinghousing 16. End plate 78 is also coupled by means of bolts 86 to thesupporting housing 12. A bearing 88 sits in a shoulder formed in the endplate 78 to facilitate relative rotation of the supporting housing 12 tothe non-supporting housing 16. The surface of the end plate 78 internalof the motor 10 is provided with a central recess 90 for seating theupstream end of the shaft 15. The shaft 15 is coupled to thenon-supporting housing 16 via the string connector 63.

As depicted most clearly in FIG. 5, when the gates 20 are in theretracted position (for example gates 20 a, 20 c and 20 e) theirrespective legs 48 overlie the inlet ports 44. The gates 20 areeffectively held in the retracted position by abutment with the lobes64. However, once out of abutment, the gates 20 are urged or indeedforced to the move to the sealing position by the pressure of theworking fluid when the holes 58 are in partial or full registration withthe inlet ports 44. As seen in FIG. 5, the valve 14 (ie shaft 15) can bearranged so in effect the inlet ports 44 are timed to be out ofalignment with the holes 58 when the gates 20 are in abutment with thelobes 64 but, are in partial or full registration when the gates 20 areout of abutment with the lobes 64.

It is further apparent that when the gates 20 are in the sealingposition they divide the sub-chambers 18 a, 18 b and 18 c into twoseparate chambers namely an induction chamber 89 and an exhaust chamber91, the respective volumes of which change dynamically as the supportinghousing 12 rotates (see FIG. 5).

The operation of the motor 10 will now be briefly described.

Working fluid (for example compressed nitrogen or other gas, or a liquidor slurry such as water or drilling mud) is channelled into the shaft 15of valve means 14 by a drill string or other equipment attached to theupstream end of the machine 10. When the holes 58 are in registrationwith the inlet ports 44, the fluid is able to pass into the inlet ports44. When the gates 20 are not in abutment with the lobes 64, thepressure of the fluid pushes the gates 20 to the sealing position andthe fluid fills an induction chamber 89 portion of the respectivesub-chamber 18 a-18 c formed between a particular gate 20 and the lobe64 it most recently passed. An exhaust chamber 91 portion of thesub-chamber is in fluid communication with the exhaust port 68.Accordingly ordinarily there will be a pressure differential in anyparticular sub-chamber between opposite sides of a gate 20. As such, theworking fluid is able to expand (if it is a gas) or otherwise act toforce the gates 20 and thus the rotor 12 to rotate in the anti-clockwisedirection. As the supporting housing 12 rotates in this directioneventually a gate 20 in the sealing position comes into abutment withthe next lobe 64. However prior to this abutment, fluid supply is cutoff to the inlet port 44 adjacent that gate by virtue of the supportinghousing 12 rotating relative to shaft 15 so that the inlet port is notin registration with any hole 58. As such, the gate 20 commences to movetoward the retracted position breaking the seal against the surface 22.The fluid previously in the induction chamber 89 is able to bypass thegate 20 and flow into the adjacent exhaust chamber 91 to be swept outthe machine via the exhaust port 68. By this time, the inlet port 44 ofthe preceding gate 20 will have come into registration with holes 58 inthe shaft 15 and, assuming that particular gate is out of abutment withthe lobe 64, the pressure of the fluid will urge the gate 20 to thesealing position and enter the next induction chamber 89. The fluid thenagain expands or acts to push the gate 20 and thus the rotor 12 in theanti-clockwise direction. In this way, the fluid drives the motor 10 tocause rotation of the supporting rotor 12 and the end plate 78 and driveshaft 83. The gas exhausted through the exhaust port 68 passes throughthe passage 84 and exits the machine 10 altogether. When used indirectional drilling a drill bit (not shown) will be coupled to thedrive shaft 83.

The cyclic alignment or registration of the holes 58 in shaft 15 and theinlet ports 44 in the supporting housing 12 forms a valve for pulsingfluid into the working chamber 18. The timing of the pulses of fluid canbe changed by varying the shape and configuration of the holes 58 in theshaft 15 and/or the shape and configuration of the radially innermostend of the inlet ports 44.

FIG. 6 illustrates a further embodiment of the machine 10 a. The machine10 a differs from the embodiment of the machine 10 depicted in FIGS. 1-5(and in particular in FIG. 5) only by the configuration of the holes 58in the shaft 15. In the machine 10 a the holes 58 have a longer arclength at their radially outermost end. Consequently, the holes 58 arein partial or full registration with the input ports 44 for a greaterperiod of time per revolution of the supporting housing 12, incomparison with the embodiment depicted in FIG. 5. In all other respectsthe machine 10 a is structurally and functionally the same as themachine 10. It will be appreciated that by appropriately configuring theholes 58 it is possible for the same hole 58 to be in fluidcommunication with two adjacent inlet ports 44 simultaneously.

FIGS. 7 and 8 illustrate a further embodiment of the machine 10 b. Theembodiment 10 b differs from that of machine 10 depicted in FIGS. 1-5 bythe provision of adjusting means to further control or vary the timingand duration of the fluid pulses into the working chamber 18. Theadjusting means in essence comprises a sleeve 92 that fits over theshaft 15. The combination of the sleeve 92 and the shaft 15 forms thevalve means 14 in this embodiment. When reviewed in transverse sectionas depicted in FIG. 8, the sleeve 92 comprises a plurality of spacedapart bands 94 of apertures 96. The bands 94 are separated by bands ofsolid material 97 having no perforations or apertures. The bands 94extend in a circumferential direction to an extent so as to be able towholly overlie the holes 58 in the shaft 55. When this occurs themaximum volume of fluid is able to flow through the valve means 14 intothe inlet port 44. By varying the rotational position of the sleeve 92relative to the shaft 15, the degree of overlap between the band ofapertures 94 with the holes 58 can be varied thereby changing thepulsing characteristics of the fluid into the inlet port 44.

In order to provide for the rotation of the sleeve 92 relative to theshaft 15 a coupling 98 is provided between the non-supporting housing16, string connector 63 and the sleeve 92. Typically the coupling 98could be made from a resilient material. The shaft 15 is fixed to thestring connector 63. The coupling 98 is sensitive to torquedifferentials between the housing 16 and the connector 63. Thus, ifthere is a difference in torque applied to the housing 16 and the stringconnector 63 they will be able to rotate relative to each other to adegree dependent upon the resilience of the coupling 98. It will beappreciated because the shaft 15 is fixed to the string connector 63 anyrelative rotation between the housing 16 and the string connector 63will be transmitted via the coupling 98 to the sleeve 92 so as to rotatethe sleeve 92 relative to the shaft 15. This will effect the relativealignment between the bands of apertures 94 with the openings 58 inshaft 15. Therefore the duration and timing of fluid pulses into theinlet ports 44 and subsequently the working chamber 18 can beautomatically adjusted in accordance with a torque differential betweenthe housing 16 and the string connector 63. This may be particularlyuseful to avoid an over speed condition in the machine 10 that mayotherwise arise if the motor 10 is lifted from the ground duringdrilling prior to shutting off the supply of fluid used to drive themachine 10.

Yet another embodiment of the machine 10 c is depicted in FIGS. 9A-9D.The machine 10 c differs from the embodiment 10 depicted in FIG. 5 interms of the exhaust porting.

In the machine 10 c, the fluid is exhausted via a exhaust porting systemthat is formed in the supporting housing 12 rather than in thenon-supporting housing 16 as depicted in FIG. 5. The exhaust system inthe machine 10 c includes a separate axial exhaust gallery 99 formed inthe supporting body 12 for each of the gates 20. The exhaust galleries99 are disposed radially inward of the gates 20. Extending transverselyfrom each exhaust gallery 99 is a row of spaced apart exhaust channels100. The channels 100 open onto the socket 28 of the nearest gate 20.Each gate 20 is also provided with an exhaust gallery 102 extendingaxially through the root portion 46. Extending transversely to thegallery 102 is a series of spaced apart first exhaust ports 104. Theports 104 open at one end onto the gallery 102 and at a distant end openonto the surface of the respective gates 20. A second set of exhaustports 106 is formed along the length of each gate 20. The ports 106extend transversely to the exhaust gallery 102 and are angularly spacedfrom the ports 104. The ports 106 open at one end onto the exhaustgallery 102 and open at the opposite end onto the surface of the root 46of each gate 20. Finally, the exhausting system includes a series ofexhaust entry ports 108 formed in the supporting housing 12. The exhaustentry ports 108 extend between the arcuate portion 42 of the outersurface of supporting housing 12 to an adjacent socket 28.

In this embodiment, the gate 20 effectively acts as a valve to open andclose the exhaust system. As shown with particular reference to gate 20a in FIG. 9C when gate 20 a is in the sealing position the exhaust ports104 and 106 are moved into registration with the exhaust entry ports 108and the exhaust channel 100 respectively so that fluid can be exhaustedvia the ports 108, 104, gallery 102, port 106, channel 100 and gallery98. However when the gates 20 are in the retracted position, for exampleas depicted by gate 20 f in FIG. 9D, the exhaust entry port 108 iseffectively sealed by the root 46 of gate 20 f thereby shutting theexhaust port. This ensures that fluid entering the inlet chamber 89 isnot able to be exhausted via the exhausting system incorporated in thegate 20 f.

FIG. 10 depicts yet another embodiment of the machine 10 d. In generalterms the embodiment of the machine 10 d is the inverse of theembodiment 10 depicted in FIG. 5. In this regard, the supporting housing12 is now the outer housing where the non-supporting housing 16 is theinner housing. As with the previous embodiments, the gates 20 arepivotally retained within sockets 28 formed in the supporting housing12. Lobes 64 are supported on the non-supporting housing 16 for movingthe gates 20 to the retracted position and also for subdividing theworking chamber 18 into sub-chamber 18 a, 18 b and 18 c. The fluid isexhausted via exhaust ports 68 formed radially in the non-supportinghousing 16 and lead to a central axial exhaust gallery 110. A furtherdifference to the machine 10 b to the previous embodiments is that thesupporting housing 12 in machine 10 d is stationary and thenon-supporting housing 16 rotates. The inlet ports in this embodimentcomprise a combination of axially extending holes 44 a and transverseholes 44 b. The axial holes 44 a are equally spaced about thecircumference of the housing 12 and are each located adjacent acorresponding socket 28. Each hole 44 a is provided with a plurality oftransverse extending smaller holes 44 b. The holes 44 b provide fluidcommunication between the holes 44 a and the respective seats 38 of eachsocket 28.

In this embodiment, the member 17 of the valve 14 is in the form of aplate 112 (see FIGS. 12 and 13) rather than the shaft 15 of the earlierembodiments. The plate 112 is disposed coaxially at an upstream end 114of the housing 12. The plate is provided with an annular feed channel116 on a side distant the end 114. The feed channel 116 provides fluidcommunication with a supply of working fluid. Channel 116 can be formedby machining a recess about the circumference of the plate 112. Theunmachined portion of the plate 112 is left as a circumferential flange118 in which is formed three arcuate slots 120. The slots 120 providefluid communication between the channel 116 and the holes 44 aconstituting part of the inlet ports of the rotary machine 10 d. Theangular length of the slots 120 determines the duration ofpressurization of a particular inlet hole 44 a. Whilst the slot 120overlies a particular hole 44 a, working fluid is able to pass into themachine 10 d via the registered slot 120 and hole 44 a. It will beappreciated that the arc length of the slots 120 can be made to providea predetermined valve timing for pulsing fluid into the machine 10 d.For example the slots 120 can be of length to ensure that at any onetime a slot is able to register with only one inlet hole 44 a. On theother hand, one or more of the slots 120 can be made of a greaterarcuate length so that at a predetermined time the slot 120 can be inregistration with two adjacent inlet port holes 44 a.

The plate 112 is also provided with a plurality of bolt holes 124 forbolting to the inner non supporting housing 16.

FIG. 13 depicts a compound rotary machine 10 e comprised of machine 10and machine 10 d coupled in series. Machine 10 is at the upstream endand machine 10 d at the downstream end. Fluid is channelled via shaft 15into the machine 10 passing through the holes 58 into inlet channels 44and subsequently into the working chamber 18 of machine 10. Thereafter,the fluid is exhausted via feed holes 72 and bore 70 of the exhaust port68 in machine 10. The exhausted fluid then forms the feed fluid or thesupply fluid for the downstream machine 10 d. Here the fluid enters thefeed channel 116 in the plate 112 and passes to the slots 120. When theslots 120 are in registration with the inlet holes 44 a in thesupporting housing 12 of machine 10 d the fluid is able to pass into theworking chamber 18. From there the fluid is exhausted through theexhaust port 68 of the machine 10 d passed through the channel 84 andout the end of the drive shaft 83. In this embodiment that the plate 112rotates with the supporting housing 12 of the machine 10 and the nonsupporting housing 16 of machine 10 d.

The series connection of the machines 10 and 10 d can improve the energyefficiency as the exhaust fluid from machine 10 that would otherwise belost or wasted is now used to drive machine 10 d.

FIG. 14 depicts a further embodiment of a compound machine 10 f thistime comprising two machines 10 coupled in series. The machines 10 areessentially in the same form as described in relation to FIGS. 1-5. Acoupling plate 126 provided between the machines 10 in order to directthe exhaust fluid from the exhaust port 68 of the upstream motor 10 tothe shaft 15 of the downstream machine 10. The plate 126 is fixed to thesupporting housing 12 and rotates therewith. In this way, the fluidcommunication between the exhaust of the upstream machine 10 to theinlet of the downstream machine 10 is maintained at all times.Otherwise, the operation of the compound machine 10 f is in substancethe same as that described in relation to machine 10.

A further embodiment of the rotary machine 10 g is illustrated in FIGS.15-17. In terms of general layout and operation the machine 10 g is insubstance the same as machine 10. However in the machine 10 g the shapeand configuration of various components have been modified.

Looking firstly at the non-supporting housing 16, the exhaust ports 68have a much larger cross-sectional area than the corresponding exhaustports in machine 10. Here, the axially extending bore 70 of the exhaustports 68 is of an irregular shape rather than circular section as inmachine 10 and additionally has a larger cross-sectional area extendingradially into the body of the non-supporting housing 16. The feed holes72 are also wider than their counterparts in machine 10. Further, abackside 65 of the lobe 64 that extends between the surfaces 66 and 22is curved rather than square as in machine 10.

The gates 20 in machine 10 g have a “swept back” or more aerodynamicshape than those of machine 10. This comes about by concavely curvingthe side of the leg 20 that contacts the peripheral surface 24 of thesupporting housing 12 when a gate is in the retracted position. Incomparison with machine 10, the corresponding side of the gate 20 is inthe form of two planar surfaces that intersect at an obtuse includedangle. Also, the gates 20 in machine 10 g are hollow, being providedwith an axial bore 128 having a cross-sectional shape somewhat similarto that of a teardrop.

The supporting housing 12 of machine 10 g has a same general form asthat in machine 10 but is of a different configuration. Starting fromthe outer peripheral surface 24, the seats 38 are arcuate rather thanplanar as in machine 10 and also the transversal arc length of the seats38 is greater than those for machine 10. Additionally, the arcuateportion 42 of the outer peripheral surface is of a shorter arc lengththan in machine 10. The sockets 28 in machine 10 g are each providedwith an arcuate portion 30 bound on one side by ridge 36 and on theopposite side by a step 34 (see the socket in which gate 20 b in FIG. 16resides). Step 34 leads to the seat 38 into which inlet port 44 opens.The ridge 36 leads to the arcuate surface 42. Further, as shown in FIG.16 the inlet ports 44 are of progressively increasing diameter in theradially outward direction. In comparison, in machine 10 as depicted inFIGS. 2 and 5, the inlet ports 44 are of uniform diameter. However, itis to be understood that in a alternate embodiment which is not shown,the ports 44 and machine 10 g can also be either of uniform or constantdiameter or indeed have a diameter that tapers in the opposite directionto that depicted. A further difference in the supporting housings 12 isthat in machine 10 g a central bore 26 is provided with six spaced apartand separate channels 130. Each channel 130 provides fluid communicationfor each respective axial banks of inlet ports 44. This assists inequalising fluid pressure especially while the gate 20 is in or near theretracted position.

The machine 10 g functions in the same manner as machine 10 although,theoretically at least, with greater efficiency. In particular, theshape of the gates 20 in machine 10 g creates better dynamic flowcharacteristics for the fluid entering the working chamber 18. When thegate 20 is being returned to the retracted position the shape of thegate allows for a cleaner flow of fluid away from the seat 38 prior tothe gate being seated. Further, due to the shape of the gate it ispossible for the fluid pressure to give the gate some radial deflectionat its tip while in the sealing position. This can assist with sealingor wear compensation.

Further, by making the gates 20 hollow, they can be made lighter andtherefore reduce the inertia to the mechanical components that arerotating, pivoting or oscillating thus providing improved efficiency andextending machine life by reducing wear. It is further envisaged thatthe bore 128 in the gates 20 could be supplied with pressurised fluidand vented around the sockets 28 to give fluid lubrication to thesockets. Alternately, the bore 128 could be filled with a resilient-typematerial with cavities projecting into the supporting housing 12 tosecure the gates in place to allow their movement in a manner akin to anartificial ligament.

The increased size of the exhaust ports 68 in machine 10 g allows formore efficient exhausting of spent fluid. Also, the tapering of theinlet ports 44 with the larger end opening onto the seat 38 allows forfluid to start expansion (when it is a gas) in the port prior toentering the working chamber. The shape of the port 44 also results inthe fluid being able to act on a greater area of the gate 20 for thepurpose of pushing or forcing the gate 20 more effectively into thesealing or extended position.

Now that embodiments of the machine 10 have been described in detail itwill be apparent to those skilled in the relevant art that numerousmodifications and variations may be made without departing from thebasic inventive concepts. For example, the machine 10 can be made withany number of gates 20 and any number of sub-chambers. Also, manydifferent arrangements can be made for valving the inlet manifold 14. Inthe embodiments depicted in FIGS. 7 and 8 the valving is effected byplacing a sleeve 92 together with a plurality of apertures 94 over theshaft 15 and providing a means for rotating the sleeve 92 relative tothe shaft. However different arrangements can be made. For example,rather than a relative rotational motion, a relative sliding motion canbe effected by use of other control means. The control means may be amechanical linkage or means for causing sliding motion of the sleeverelative to the shaft 15 by virtue of fluid pressure. Further, insteadof the valve operating on the basis of a torque differential it mayoperate on the basis of rotational speed of the inner housing so as toprogressively restrict the flow of fluid into the machine 10 as speedincreases.

All such modifications and variations together with others that would beobvious to a person of ordinary skill in the art are deemed to be withinthe scope of the present invention the nature of which is to bedetermined from the above description.

1. A rotary machine including at least: an inner housing; an outerhousing in which the inner housing resides, one of the inner and outerhousings being rotatable relative to another of the inner and outerhousings, with a working chamber through which a working fluid flowsbeing defined between the inner housing and the outer housing; aplurality of gates supported by one of the inner housing and the outerhousing, wherein the housing supporting the gates constitutes asupporting housing and the housing not supporting the gates constitutesa non-supporting housing, each gates swingable along its respectivelongitudinal axis between a sealing position in which the gates form aseal against a surface of non-supporting housing and a retractedposition in which the gates lie substantially against a surface of thesupporting housing facing the working chamber, said supporting housingprovided with a plurality of inlet ports through which the working fluidflows into the working chamber; a plurality of lobes supported by thenon-supporting housing and which form a seal against a facing surface ofthe supporting housing thereby dividing the working chamber into aplurality of sub-chambers, each lobe defining an exhaust port forexhausting the working fluid from an adjacent sub-chamber wherein eachof the exhaust ports comprising an axially extending bore formed througheach of the lobes and a plurality of feed holes that passes through eachof the lobes for communicating the working fluid between the workingchamber and the bore; and a valve operatively associated with saidsupporting housing that directs said working fluid into the workingchamber via the support housing, the valve comprising a shaft extendingcoaxially into and rotatable relative to the supporting housing, theshaft having an axial passage in fluid communication with a supply ofsaid working fluid and a plurality of radially extending holes providingfluid communication between said axial passage and the inlet ports inthe supporting housing for a predetermined period of time per revolutionof the shaft relative to the supporting housing.
 2. The rotary machineaccording to claim 1, wherein the supporting housing is further providedwith a plurality of sockets extending longitudinally along its surfacefacing the working chamber and each gate is pivotally retained andsupported in a respective socket to facilitate the swinging motion ofthe gates.
 3. The rotary machine according to claim 2, wherein thesockets and the gates are complementarily shaped so that when the gatesare in the retracted position their radially outermost surface liessubstantially flush with, or below, the surface of the supportinghousing facing the working chamber.
 4. The rotary machine according toclaim 3, wherein each socket and each gate is provided with a first setof respective stop surfaces that come into mutual abutment when thegates swing to the sealing position from the retracted position.
 5. Therotary machine according to claim 4, wherein each socket and gate isprovided with a second set of respective stop surfaces spaced from thefirst set of stop surfaces have come into mutual abutment when the gatesswing to the sealing position from the retracted position.
 6. The rotarymachine according to claim 5, wherein said first and second sets ofrespective stop surfaces are positioned so as to come into respectivemutual contacts substantially simultaneously.
 7. The rotary machineaccording to claim 6, wherein said lobes form a seal against the surfaceof the supporting housing facing the working chamber to divide theworking chamber into a plurality of sub-chambers, and wherein said lobesforce said gates toward said retracted position upon engagement withsaid gates.
 8. The machine according to claim 6, wherein the supportinghousing is provided with a plurality of inlet ports providing fluidcommunication between the valve and the working chamber.
 9. The machineaccording to claim 8, wherein each inlet port has an opening into saidworking chamber and said gates are arranged to overlie said opening whenin the retracted position wherein fluid passing through the inlet porturges said gate toward said sealing position.
 10. A rotary machinecomprising: an inner housing; an outer housing in which the innerhousing resides, one of the inner and outer housings being rotatablerelative to another of the inner and outer housings, with a workingchamber through which a working fluid flows being defined between theinner housing and the outer housing; a plurality of gates supported byone of the inner housing and the outer housing, wherein the housingsupporting the gates constitutes a supporting housing and the housingnot supporting the gates constitutes a non-supporting housing, each gateswingable along its respective longitudinal axis between a sealingposition in which the gates form a seal against a surface of thenon-supporting housing, and a retracted position in which the gates liesubstantially against a surface of the supporting housing facing theworking chamber; a plurality of lobes supported by the non-supportinghousing and which form a seal against a facing surface of the supportinghousing thereby dividing the working chamber into a plurality ofsub-chambers, each lobe defining an exhaust port for exhausting theworking fluid from an adjacent sub-chamber wherein each of the exhaustports comprising an axially extending bore formed through each of thelobes and a plurality of feed holes that passes through each of thelobes for communicating the working fluid between the working chamberand the bore; and valve means operatively associated with saidsupporting housing for directing working fluid into said working chambervia said support housing, said valve means comprising a member locatedco-axially with and rotatably relative to said supporting housing, saidmember having a passage or channel in communication with a supply ofworking fluid and a plurality of holes providing fluid communicationbetween said passage or channel and said working chamber for apredetermined period of time per revolution of said supporting housingrelative to said valve means.
 11. The rotary machine according to claim10, wherein the supporting housing is provided with a plurality ofsockets extending longitudinally along its surface facing the workingchamber and each gate is pivotally retained and supported in arespective socket to facilitate the swinging motion of the gates. 12.The rotary machine according to claim 11, wherein the sockets and thegates are complementarily shaped so that when the gates are in theretracted position their radially outermost surface lies substantiallyflush with, or below, the surface of the supporting housing facing theworking chamber.
 13. The rotary machine according to claim 12, whereineach socket and each gate is provided with a first set of respectivestop surfaces that come into mutual abutment when the gates swing to thesealing position from the retracted position.
 14. The rotary machineaccording to claim 13, wherein each socket and gate is provided with asecond set of respective stop surfaces spaced from the first set of stopsurfaces have come into mutual abutment when the gates swing to thesealing position from the retracted position.
 15. The rotary machineaccording to claim 14, wherein said first and second sets of respectivestop surfaces are positioned so as to come into respective mutualcontact substantially simultaneously.
 16. The rotary machine accordingto claim 15, wherein the supporting housing is provided with a pluralityof inlet ports providing fluid communication between said passage orchannel and the working chamber.
 17. The rotary machine according toclaim 16, wherein each inlet port has an opening into said workingchamber and said gates are arranged to overlie said opening when in theretracted position wherein fluid passing through the inlet port urgessaid gate toward said sealing position.
 18. The rotary machine accordingto claim 17, wherein said lobes form a seal against the surface of thesupporting housing facing the working chamber to divide the workingchamber into a plurality of sub-chambers, and wherein said lobes forcesaid gates toward said retracted position upon engagement with saidgates.
 19. The rotary machine according to claim 10 wherein said memberis a shaft which extends co-axially through said supporting housing andsaid passage extends axially into said shaft.
 20. A rotary machinecomprising: an inner housing; an outer housing in which the innerhousing resides, one of the inner and outer housings being rotatablerelative to another of the inner and outer housings, with a workingchamber through which a working fluid flows being defined between theinner housing and the outer housing; a plurality of gates supported byone of the inner housing and the outer housing, wherein the housingsupporting the gates constitutes a supporting housing and the housingnot supporting the gates constitutes a non-supporting housing, each gateswingable along its respective longitudinal axis between a sealingposition in which the gates form a seal against a surface of thenon-supporting housing and a retracted position in which the gates liesubstantially against a surface of the supporting housing facing theworking chamber; and a valve operatively associated with said supportinghousing that directs said working fluid into the working chamber via thesupport housing, said valve providing fluid communication between asupply of said working fluid and said working chamber for apredetermined period of time per revolution of said supporting housingrelative to said valve; said supporting housing being provided with aplurality of inlet ports providing fluid communication between saidvalve and said working chamber, wherein each inlet port has an openinginto said working chamber and said gates are arranged to overlie saidopening when in the retracted position wherein fluid passing throughsaid inlet port urges said gate toward said sealing position, aplurality of lobes supported by the non-supporting housing and whichform a seal against a facing surface of the supporting housing therebydividing the working chamber into a plurality of sub-chambers, each lobedefining an exhaust port for exhausting the working fluid from anadjacent sub-chamber wherein each of the exhaust ports comprising anaxially extending bore formed through each of the lobes and a pluralityof feed holes that passes through each of the lobes for communicatingthe working fluid between the working chamber and the bore, the valvecomprising a shaft extending coaxially into and rotatable relative tothe supporting housing, the shaft having an axial passage in fluidcommunication with a supply of said working fluid and a plurality ofradially extending holes providing fluid communication between saidaxial passage and the inlet ports in the supporting housing for apredetermined period of time per revolution of the shaft relative to thesupporting housing.
 21. A rotary machine comprising: a supportinghousing; a non-supporting housing in which the supporting housingresides, one of the supporting and the non-supporting housings beingrotatable relative to another and concentric with each other, with aworking chamber through which a working fluid flows being definedbetween the supporting housing and the non-supporting housing; aplurality of gates supported by the supporting housing, each gateswingable along its respective longitudinal axis between a sealingposition in which the gates form a seal against a surface of thenon-supporting housing and a retracted position in which the gates areswung about their longitudinal axes to lie substantially against asurface of the supporting housing facing the working chamber, saidsupporting housing provided with a plurality of inlet ports throughwhich the working fluid flows into the working chamber; a plurality oflobes supported by the non-supporting housing and which form a sealagainst a facing surface of the supporting housing, thereby dividing theworking chamber into a plurality of sub-chambers, each lobe defining anexhaust port for exhausting the working fluid from an adjacentsub-chamber wherein each of the exhaust ports comprising an axiallyextending bore formed through each of the lobes and a plurality of feedholes that passes through each of the lobes for communicating theworking fluid between the working chamber and the bore; and a valveoperatively associated with the supporting housing for directing workingfluid into the sub-chambers via the support housing, the valvecomprising a member located coaxially with and rotatable relative to thesupporting housing, the member having a passage or channel incommunication with a supply of working fluid and a plurality of holesproviding fluid communication between the passage or channel and theinlet ports for a predetermined period of time per revolution of thesupporting housing relative to the valve.
 22. The machine according toclaim 21, wherein the supporting housing is provided with a plurality ofsockets extending longitudinally along its surface facing the workingchamber and each gate is pivotally retained and supported in arespective socket to facilitate the swinging motion of the gates. 23.The machine according to claim 22, wherein the sockets and the gates arecomplementarily shaped so that when the gates are in the retractedposition their radially outermost surface lies substantially flush with,or below, the surface of the supporting housing facing the workingchamber.
 24. The machine according to claim 23, wherein each socket andeach gate is provided with a first set of respective stop surfaces thatcome into mutual abutment when the gates swing to the sealing positionfrom the retracted position.
 25. The machine according to claim 24,wherein each socket and each gate is provided with a second set ofrespective stop surfaces spaced from the first set of stop surfaces thatcome into mutual abutment when the gates swing to the sealing positionfrom the retracted position.
 26. The machine according to claim 25,wherein the first and the second sets of respective stop surfaces arepositioned so as to come into respective mutual contact substantiallysimultaneously.
 27. The machine according to claim 21, wherein eachinlet port has an opening into said working chamber and said gates arearranged to overlie said opening when in the retracted position whereinfluid passing through the inlet port urges said gate toward said sealingposition.
 28. The machine according to claim 21, wherein the lobes areconfigured to force the gates toward the retracted position uponengagement of the lobes with the gates.
 29. The machine according toclaim 21, wherein the valve is provided with an adjuster to facilitateadjustment of the flow of the working fluid into the working chamber.30. The machine according to claim 29, wherein said member comprises ashaft that extends coaxially through the supporting housing and thepassage extends axially into the shaft.
 31. The machine according toclaim 30, wherein the adjuster comprises a sleeve located coaxially withthe shaft and movable relative to the shaft, the sleeve provided withone or more apertures extending radially therethrough, and a device foreffecting movement of the sleeve relative to the shaft to allowvariation in overlap or alignment of the apertures and the holes tothereby control the flow of the working fluid from the supply to theworking chamber.
 32. The machine according to claim 31, wherein thedevice for effecting movement comprises a coupling acting between thenon-supporting housing, a connector for connecting the rotary machine toa supporting apparatus and one of the shaft and the sleeve, whereby atorque differential between the non-supporting housing and thesupporting apparatus is transmitted by the coupling to act between thesleeve and the shaft to effect the movement of the sleeve relative tothe shaft.
 33. The machine according to claim 21, wherein the membercomprises a plate disposed coaxially of the non-supporting housing, thechannel provided on a side of the plate distant from the supportinghousing and the holes comprise slots cut in an axial direction throughthe plate for providing fluid communication between the channel and theworking chamber for a predetermined period of time per revolution of theplate relative to the supporting housing.